Peierls distorted chain as a quantum data bus for quantum state transfer

TL;DR

This paper investigates using a Peierls distorted SSH chain as a quantum data bus for transferring electron spin states, leveraging the energy gap to enhance robustness and enable quantum communication with always-on interactions.

Contribution

It introduces a novel quantum state transfer mechanism utilizing the Peierls energy gap in the SSH model, providing robustness and new insights into quantum communication protocols.

Findings

The SSH chain can effectively transfer quantum states via quasi-excitations.

The Peierls energy gap protects the robustness of quantum state transfer.

The scheme enables quantum communication with always-on interactions.

Abstract

We systematically study the transfer of quantum state of electron spin as the flying qubit along a half-filled Peierls distorted tight-binding chain described by the Su-Schrieffer-Heeger (SSH) model, which behaves as a quantum data bus. This enables a novel physical mechanism for quantum communication with always-on interaction: the effective hopping of the spin carrier between sites $A$ and $B$ connected to two sites in this SSH chain can be induced by the quasi-excitations of the SSH model. As we prove, it is the Peierls energy gap of the SSH quasi-excitations that plays a crucial role to protect the robustness of the quantum state transfer process. Moreover, our observation also indicates that such a scheme can also be employed to explore the intrinsic property of the quantum system.